Ultrasound operation apparatus, ultrasound operation system, and cavitation utilization method

ABSTRACT

An ultrasound operation apparatus includes an ultrasound transducer; a drive section that drives the ultrasound transducer by means of a drive signal; a probe that has a proximal end section in which the ultrasound transducer is provided and a distal end section to which ultrasound vibrations are transmitted, and that performs treatment for living tissue by using ultrasound vibrations at the distal end section; a detection section that detects from the drive signal a physical quantity that changes due to cavitations generated by ultrasound vibrations of the distal end section and an output control section that controls the output of the drive section so as to generate cavitations or to increase or maintain a generation amount in accordance with the detected physical quantity.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an ultrasound operation apparatus thatperforms an operation utilizing ultrasound vibrations and also utilizescavitations that are generated accompanying ultrasound vibrations, aswell as an ultrasound operation system and a cavitation utilizationmethod.

2. Description of the Related Art

Ultrasound operation apparatuses that perform an operation on livingtissue utilizing ultrasound vibrations produced by an ultrasoundtransducer have been widely used in recent years. When living tissue iscaused to vibrate at an ultrasound frequency, in some cases cavitationsare generated since the living tissue includes liquid. A cavitationindicates that when the pressure of a liquid becomes lower than a vaporpressure that is decided by the temperature of the liquid, the liquidevaporates and vapor bubbles are produced.

Accordingly, when compression waves are generated by ultrasoundvibrations, cavitations are generated accompanying the generation ofnegative pressure.

Therefore, for example, Japanese Patent Application Laid-OpenPublication No. 2002-537955 discloses an apparatus that irradiatesultrasound for medical treatment at a location inside the body, andmonitors the level of cavitations at that time using a hydrophone.

Further, International Publication No. WO2005/094701 discloses anapparatus in which a sound pressure signal receiving probe is providedin a piezoelectric element for ultrasound irradiation, and whichcontrols ultrasound irradiation conditions by means of sound pressuresignals that are discharged from cavitation bubbles by the soundpressure signal reception probe.

SUMMARY OF THE INVENTION

An ultrasound operation apparatus according to one aspect of the presentinvention includes:

an ultrasound transducer that is capable of generating ultrasoundvibrations;

a drive section that drives the ultrasound transducer by means of adrive signal;

a probe that has a proximal end section that is operationally coupledwith the ultrasound transducer, and a distal end section that generatesultrasound vibrations for treating a tissue, the probe being used fortransmitting the ultrasound vibrations generated by the ultrasoundtransducer from the proximal end section to the distal end section;

a detection section that detects a physical quantity that changes due toa cavitation generated by ultrasound vibrations of the distal endsection of the probe from the drive signal; and

a cavitation generation control section that, in accordance with thephysical quantity that is detected by the detection section, controls anoutput of the drive section so as to generate cavitations by means ofultrasound vibrations of the distal end section or to increase ormaintain a generation amount.

An ultrasound operation apparatus according to another aspect of thepresent invention includes:

an ultrasound transducer that is capable of generating ultrasoundvibrations;

a drive section that drives the ultrasound transducer by means of adrive signal;

a probe that has a proximal end section that is operationally coupledwith the ultrasound transducer, and a distal end section that generatesultrasound vibrations for treating a living tissue, the probe being usedfor transmitting the ultrasound vibrations generated by the ultrasoundtransducer from the proximal end section to the distal end section;

a resonance frequency tracking section that automatically adjusts afrequency of the drive signal so that the ultrasound transducer tracks aresonance frequency of the ultrasound transducer, to cause the distalend section to make ultrasound vibrations at the resonance frequency;

a detection section that detects a cavitation by detecting a frequencycomponent signal of a frequency component other than a resonancefrequency of the drive signal; and

a cavitation generation control section that performs control thatchanges the drive signal that drives the ultrasound transducer so as togenerate cavitations or to increase or maintain a generation amount inaccordance with a detection result of the frequency component signalthat is detected by the detection section.

An ultrasound operation system according to a further aspect of thepresent invention includes:

an ultrasound transducer that is capable of generating ultrasoundvibrations;

a drive section that drives the ultrasound transducer;

a proximal end section that is operationally coupled with the ultrasoundtransducer, and a resonance frequency tracking section that tracks aresonance frequency of the ultrasound transducer for treating a tissue;

a distal end section that generates ultrasound vibrations at the trackedresonance frequency;

a probe for transmitting the ultrasound vibrations that are generated bythe ultrasound transducer from the proximal end section to the distalend section;

a suction driving section that sucks a liquid in a vicinity of thedistal end section;

a suction amount detection section that detects a suction amount that issucked by the suction driving section;

a suction amount setting section that sets the suction amount;

a suction control section that controls the suction driving section inaccordance with the suction amount setting section; and

a cavitation generation control section that controls the dUrive signalso as to maintain a cavitation in accordance with a detection result ofthe suction amount detection section.

A cavitation utilization method according to a further aspect of thepresent invention includes:

a step of applying ultrasound vibrations to a treatment target portionby means of an ultrasound transducer that is capable of generatingultrasound vibrations; a drive section that drives the ultrasoundtransducer with a drive signal; and a probe that has a proximal endsection that is operationally coupled with the ultrasound transducer,and a distal end section that generates ultrasound vibrations fortreating a tissue, the probe being used for transmitting the ultrasoundvibrations generated by the ultrasound transducer from the proximal endsection to the distal end section;

a cavitation detection step of detecting a physical quantity thatchanges due to a cavitation generated by ultrasound vibrations of thedistal end section of the probe; and

a cavitation generation control step of controlling the drive signal soas to generate a cavitation or to increase or maintain a generationamount in accordance with a detection result of the cavitation detectionstep.

A cavitation utilization method according to a further aspect of thepresent invention includes:

a step of applying ultrasound vibrations to a treatment target portionby means of an ultrasound transducer that is capable of generatingultrasound vibrations; a drive section that drives the ultrasoundtransducer with a drive signal; and a probe that has a proximal endsection that is operationally coupled with the ultrasound transducer,and a distal end section that generates ultrasound vibrations fortreating a tissue, the probe being used for transmitting the ultrasoundvibrations generated by the ultrasound transducer from the proximal endsection to the distal end section;

a resonance frequency tracking step of automatically adjusting afrequency of the drive signal so as to track a resonance frequency ofthe ultrasound transducer;

a detection step of detecting a frequency component signal other than aresonance frequency of the drive signal; and

a cavitation generation control step of controlling the drive signal soas to generate a cavitation or to increase or maintain a generationamount in accordance with a detection result of the detection step.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a configuration diagram that illustrates a configuration of anultrasound operation system that includes a first embodiment of thepresent invention;

FIG. 2 is a configuration diagram of an ultrasound operation apparatusaccording to the first embodiment;

FIG. 3 is a block diagram that illustrates a configuration of anultrasound driving apparatus in the ultrasound operation apparatus;

FIG. 4A is a view that illustrates a frequency distribution of a currentsignal that is detected from a drive signal at a time of cavitationgeneration and a time when a cavitation is not generated;

FIG. 4B to FIG. 4D are views that illustrate characteristic examplesthat show frequency bands that a filter circuit allows to passtherethrough;

FIG. 5 is a block diagram that illustrates a configuration example of afilter circuit;

FIG. 6 is a flowchart that illustrates an operation method that utilizescavitations generated by an ultrasound operation apparatus;

FIG. 7 is a flowchart that illustrates a method of controlling thegeneration level of cavitations in FIG. 6;

FIG. 8 is a block diagram that illustrates a configuration of anultrasound driving apparatus in an ultrasound operation apparatusaccording to a second embodiment of the present invention;

FIG. 9 is a flowchart that illustrates a control method according to thesecond embodiment;

FIG. 10 is a configuration diagram of an ultrasound operation apparatusaccording to a third embodiment of the present invention;

FIG. 11 is a view that illustrates a setting section that selectivelysets a plurality of control modes;

FIG. 12 is a flowchart that illustrates one example of a control methodof an ultrasound operation apparatus according to the third embodiment;

FIG. 13 is a configuration diagram of an ultrasound operation apparatusaccording to a first modification example;

FIG. 14 is a flowchart illustrating a control method according to thefirst modification example;

FIG. 15 is a configuration diagram of an ultrasound operation apparatusaccording to a second modification example;

FIG. 16 is a view that shows an outline of principal parts of anultrasound operation apparatus according to a third modificationexample;

FIG. 17 is a flowchart that illustrates a control method according tothe third modification example;

FIG. 18 is a block diagram that illustrates a configuration of anultrasound operation system including a fourth embodiment of the presentinvention;

FIG. 19 is a flowchart that illustrates one example of a control methodaccording to the fourth embodiment;

FIG. 20A is a view that illustrates a shape of a distal end section of aprobe that is used in a fifth embodiment of the present invention;

FIG. 20B is a view that illustrates a state in which a cavitation isproduced by ultrasound vibrations of a concavo-convex section;

FIG. 20C to FIG. 20E are views that illustrate modification examples ofthe distal end section;

FIG. 21 is a block diagram that illustrates a configuration of anultrasound operation apparatus according to the fifth embodiment; and

FIG. 22A and FIG. 22B are views that illustrate sequences that switch acontrol mode and drive in a case of performing treatment by ultrasoundaccording to the fifth embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereunder, embodiments of the present invention are described withreference to the drawings.

First Embodiment

FIG. 1 to FIG. 8 relate to a first embodiment of the present invention.FIG. 1 illustrates a configuration of an ultrasound operation systemthat includes the first embodiment of the present invention. FIG. 2illustrates a configuration of an ultrasound operation apparatusaccording to the first embodiment. FIG. 3 illustrates a configuration ofan ultrasound driving apparatus. FIG. 4A illustrates a frequencydistribution of a current signal that is detected from a drive signal ata time of cavitation generation and a time when a cavitation is notgenerated. In this case, although the frequency distribution of acurrent signal is shown, a similar distribution is obtained with avoltage signal also.

FIG. 4B to FIG. 4D illustrate examples of filter characteristics of afilter circuit. FIG. 5 illustrates a configuration example of a filtercircuit. FIG. 6 illustrates an operation method that utilizescavitations generated by an ultrasound operation apparatus. FIG. 7illustrates a method of controlling so as to maintain the generationlevel of cavitations in FIG. 6.

As shown in FIG. 1, an ultrasound operation system 1 equipped with thefirst embodiment of the present invention has a first handpiece 2 as anultrasound coagulation/dissection treatment instrument that performs atreatment such as coagulation and dissection as well as exfoliatingdissection by ultrasound, a second handpiece 3 as an ultrasound/suctiontreatment instrument that performs a treatment such as dissection,exfoliation dissection, or crushing by ultrasound and also a suctionoperation, and a third handpiece 4 as an ultrasound puncture treatmentinstrument that performs a treatment such as puncturing by ultrasound.

Further, the ultrasound operation system 1 includes an ultrasounddriving apparatus 5 that has a drive section that applies (outputs) anultrasound drive signal to any handpiece that is actually connectedamong the first to third handpieces, a high frequency output apparatus 6that applies a high frequency output signal to a handpiece that isactually connected among the first handpiece 2 and the second handpiece3, and a water supply/suction device 7 that performs water supply andsuction operations in the case of the second handpiece 3.

Foot switches 8, 9, and 10 are connected to the ultrasound drivingapparatus 5, the high frequency output apparatus 6, and the watersupply/suction device 7, respectively, and switch the output of therespective apparatuses “on” and “off”.

The ultrasound driving apparatus 5 and the high frequency outputapparatus 6 are connected by a communication cable 11 that performscommunication. The ultrasound driving apparatus 5 and the watersupply/suction device 7 are connected by a communication cable 12. Thehigh frequency output apparatus 6 and the water supply/suction device 7are connected by a communication cable 13.

Each of the handpieces I (I=2, 3, 4) among the first handpiece 2 to thethird handpiece 4 includes an elongated probe 2 a, 3 a, and 4 a,respectively, and also includes an ultrasound transducer (hereunder,referred to simply as “transducer”) Ib capable of generating ultrasoundvibrations inside a grasping section. A proximal end section of eachprobe Ia is disposed at the grasping section. Ultrasound vibrationsgenerated by the transducer Ib are operationally coupled (that is,coupled so that ultrasound vibrations can be transmitted to the proximalend section) to, for example, a horn that is provided with an expandeddiameter at the proximal end section of each of the probes Ia.

An ultrasound connector Ic that is electrically connected to thetransducer Ib is provided at the proximal end of each handpiece I. Theultrasound connector Ic is connected to the ultrasound driving apparatus5 via a detachable ultrasound cable 14.

When a surgeon switches the foot switch 8 “on”, the ultrasound drivingapparatus 5 outputs an ultrasound drive signal (hereafter, abbreviatedto “drive signal”) to the transducer Ib via the ultrasound cable 14. Thetransducer Ib generates ultrasound vibrations when the drive signal isapplied thereto.

The transducer Ib transmits ultrasound vibrations to a distal end memberIe as a distal end section of the probe Ia through an ultrasoundtransmitting member Id inside the probe Ia, and the distal end member Ievibrates at an ultrasound frequency.

The surgeon can perform treatment using ultrasound vibrations by, forexample, grasping the grasping section on the proximal end side of ahandpiece and contacting the distal end member Ie that vibrates at anultrasound frequency against a living tissue that is a treatment target.

Further, a high frequency connector 2 f provided on the proximal endside of the handpiece 2 or a high frequency connector 3 f of thehandpiece 3 is connected to the high frequency output apparatus 6 via adetachable high frequency cable 15. When the surgeon switches the footswitch 9 “on”, the high frequency output apparatus 6 outputs a highfrequency output signal to a conductor section inside the handpiece viaa high frequency cable 15. The conductor section is formed with theultrasound transmitting member Id. Similarly to the case of ultrasoundvibrations, the high frequency output signal is transmitted to thedistal end member Ie of the distal end section of the probe Ia.

When the surgeon brings the distal end member Ie into contact with theliving tissue, an electric current (high frequency current) of the highfrequency output signal flows to the living tissue side. By means of thehigh frequency current, the surgeon performs high-frequencycauterization treatment with respect to the living tissue portion thatis contacted.

In this case, the patient is disposed so as to contact over a wide areawith a counter-electrode plate (not shown), and the high frequencycurrent that flows through the living tissue is returned via thecounter-electrode plate to the high frequency output apparatus 6 througha return cable that is connected to the counter-electrode plate.

Further, in the handpiece 3, the ultrasound transmitting member 3 d isformed with a conduit, and a hollow section of the conduit serves as asuction passage (water supply is performed between the conduit of theultrasound transmitting member 3 d and an outer sheath (not shown)). Thedistal end member 3 e that serves as the distal end of the conduit isopen.

A water supply/suction connector 3 g is provided on the proximal endside of the handpiece 3. A water supply/suction tube 16 that isdetachably connected to the handpiece 3 is connected to the watersupply/suction device 7.

The water supply/suction tube 16, for example, branches into a watersupply conduit and a suction conduit inside the water supply/suctiondevice 7, and the water supply conduit connects to a water supplyapparatus and the suction conduit connects to a suction apparatus.

When the surgeon performs an operation to switch “on” a water supplyswitch of the foot switch 10, a water supply pump that is included inthe water supply apparatus is activated and feeds water. The fed waterpasses through a hollow section forming the ultrasound transmittingmember 3 d and is ejected from an opening of the distal end member 3 e.

Further, when the surgeon performs an operation to switch “on” a suctionswitch of the foot switch 10, a suction pump that is included in thesuction apparatus is activated and performs a suction action. Thereupon,tissue pieces and the like that are produced at the time of treatment(crushing with ultrasound vibrations) are sucked from the opening of thedistal end member 3 e and discharged to the suction apparatus.

Although FIG. 1 shows a configuration example for a case of performingtreatment by also using a function other than ultrasound vibrations, asshown in FIG. 2, an ultrasound operation apparatus 21 may also beconfigured that performs treatment utilizing only ultrasound vibrations.

The ultrasound operation apparatus 21 shown in FIG. 2 includes, forexample, the handpiece 2 that performs coagulation/dissection treatmentby ultrasound vibrations, an ultrasound driving apparatus 5 that outputsa drive signal to the handpiece 2, and a foot switch 8 that is connectedto the ultrasound driving apparatus 5 and switches the output of a drivesignal “on” and “off”. The handpiece 2 is connected to a connector 22 ofthe ultrasound driving apparatus 5 via an ultrasound cable 14.

In this connection, instead of the handpiece 2, the handpiece 3 or thehandpiece 4 may be connected to the ultrasound driving apparatus 5.Further, as described in an embodiment mentioned below, a configurationmay also be adopted in which treatment is performed in combination withuse of the high frequency output apparatus 6.

As shown in FIG. 2, the handpiece 2 is provided with a handle 18 on theproximal end side thereof. The surgeon grasps the handle 18 and performsan opening/closing operation.

In the handle 18, the upper end side of a moveable handle 19 a isrotatably supported at a pivot section.

By performing an opening/closing operation that closes the moveablehandle 19 a to a fixed handle 19 b side or opens the moveable handle 19a to a side away from the fixed handle 19 b, a moveable distal endmember 2 g that is rotatably supported adjacent to the distal end member2 e can be opened/closed with respect to the distal end member 2 ethrough an unshown wire that is passed through the inside of the probe 2a.

Thus, the handpiece 2 can be opened and closed so as to grasp livingtissue by means of the distal end member 2 e as a fixed distal endmember and the moveable distal end member 2 g.

More specifically, by applying ultrasound vibrations to living tissue ina state in which the living tissue is grasped by the distal end members2 e and 2 g, the handpiece 2 can generate frictional heat in the livingtissue and perform coagulation or dissection treatment of the livingtissue that is grasped. It is also possible to set the handpiece 2 in anopen state in which the distal end side is opened, and perform treatmentsuch as crushing by means of the protruding distal end member 2 e.

On a front panel of the ultrasound driving apparatus 5 are provided adisplay section 23 that shows a display, and a setting section 24 thatsets a setting value of a signal to be outputted as an ultrasound drivesignal and the like.

FIG. 3 illustrates a configuration of the ultrasound driving apparatus 5that is included in the ultrasound operation apparatus 21 according tothe present embodiment. In this connection, FIG. 3 shows the fundamentalcomponent parts of the handpiece 2 (the situation is substantially thesame for the handpieces 3 and 4) that is connected to the ultrasounddriving apparatus 5. Hereunder, although a description is given for acase in which I=2 as the handpiece I, the following description can alsobe applied to cases in which I=3 or I=4, excluding a structure that isunique to the handpiece 2.

The ultrasound driving apparatus 5 has an oscillating circuit 31, amultiplier 32 into which an oscillation signal that is generated by theoscillating circuit 31 is inputted from one input end, an amplifier 33that amplifies a signal that is multiplied by the multiplier 32, and anoutput circuit 34 that isolates and outputs a drive signal that isamplified by the amplifier 33.

The output circuit 34 includes, for example, a transformer 34 a. A drivesignal that is amplified at the amplifier 33 is inputted to a primarywinding of the transformer 34 a. A drive signal that is isolated fromthe drive signal on the primary winding is outputted from a secondarywinding that is electromagnetically coupled with the primary winding. Inthis connection, the primary winding side of the transformer 34 a formsa secondary circuit, and the secondary winding side thereof forms apatient circuit.

A connector 22 of an output terminal from which a drive signal isoutputted on the patient circuit side is connected via detachablyconnected ultrasound cables 14 with a transducer 2 b that is containedinside the handpiece 2 that vibrates at an ultrasound frequency.

Further, the primary winding of the transformer 34 a is connected with acurrent/voltage detecting circuit 35 that detects a current of a drivesignal flowing to the primary winding and a voltage at both endsthereof, and also detects a phase of the current and a phase of thevoltage.

A current phase signal θi and a voltage phase signal θv detected by thecurrent/voltage detecting circuit 35 are outputted to a PLL(phase-locked loop) circuit 36.

The PLL circuit 36 applies a control signal to the oscillating circuit31. In the control signal, the signal level that is outputted changes inaccordance with a phase difference between the current phase signal θiand the voltage phase signal θv that are inputted to the PLL circuit 36.At the oscillating circuit 31, an oscillation frequency changes with asignal level that is applied to a control inputted end. That is, theoscillating circuit 31 is formed, for example, by a voltage-controlledoscillator (VCO).

The PLL circuit 36 applies a control signal that controls so as toreduce the phase difference between the current phase signal θi and thevoltage phase signal θv, more specifically, an oscillation frequencyadjusting signal that is described below, to the control input end ofthe oscillating circuit 31. Accordingly, at the oscillating circuit 31,by means of a closed loop using the PLL circuit 36, the oscillationfrequency is automatically adjusted so that a phase difference betweenthe current phase signal θi and the voltage phase signal θv becomes 0.

A state in which the phase difference between the current phase signalθi and the voltage phase signal θv becomes 0 is a drive frequency thatcorresponds to a resonance frequency of the transducer 2 b. Therefore,the PLL circuit 36 automatically adjusts (controls) the oscillationfrequency so as to drive the transducer 2 b with a drive signal at theresonance frequency of the transducer 2 b.

In other words, when driving the transducer 2 b with a drive signal, theclosed-loop circuit system between the oscillating circuit 31 and thePLL circuit 36 forms a resonance frequency tracking section 37 thatautomatically adjusts the frequency of the drive signal so as to trackthe resonance frequency of the transducer 2 b. The resonance frequencytracking section 37 constitutes a drive section that outputs a drivesignal at the resonance frequency.

The present embodiment is also provided with a detection section 38that, as described below, detects a cavitation that is generated withthe distal end member 2 e of the probe 2 a (to which ultrasoundvibrations of the transducer 2 b are transmitted) based on a drivesignal of the primary winding side of the aforementioned output circuit34 from a drive signal as a physical quantity that changes as a resultof the cavitation.

For example, a voltage signal Sv as a physical quantity that changes asa result of a cavitation in a drive signal is inputted into a filtercircuit 39 that has frequency transmission characteristics (filtercharacteristics) for extracting a predetermined frequency component. Inthis connection, as mentioned later, the current in the drive signal iscontrolled so as to become a constant current with a predetermined timeconstant. Therefore, detecting a voltage value (that passed through thefilter circuit 39) in the voltage signal Sv is approximately equivalentto detecting an impedance value.

In this connection, in addition to detecting a voltage value or animpedance value as the aforementioned physical quantity, the detectionsection 38 may also be configured to detect a current value of a currentsignal. In this case, for example, a configuration may be adopted so asto perform detection in a state in which the voltage signal Sv iscontrolled so as to become a constant voltage with a predetermined timeconstant.

The filter circuit 39 has characteristics such that a predeterminedfrequency component other than at least a resonance frequency (i.e.drive frequency) of the transducer 2 b that is driven by the drivesignal passes therethrough.

A voltage signal as a frequency component signal of a predeterminedfrequency component that is outputted from the filter circuit 39 becomesa detection signal that corresponds to the generation level ofcavitations that are generated with the transducer 2 b, i.e. acavitation level signal Sc.

The cavitation level signal Sc that is outputted from the filter circuit39 is inputted to a central processing unit (CPU) 40 as a controlsection that performs control of each section of the ultrasound drivingapparatus 5.

The aforementioned detection section 38 is constituted using the filtercircuit 39 that generates the cavitation level signal Sc. In thisconnection, the detection section 38 can also be regarded as having aconfiguration that includes the CPU 40 that determines theexistence/non-existence of a cavitation based on the cavitation levelsignal Sc, and determines the level of cavitation generation.

Further, the CPU 40 also functions as an output control section thatvariably controls an output value of a drive signal that determines theamplitude of ultrasound vibrations at the distal end member 2 e of theprobe 2 a based on the physical quantity that is detected by thedetection section 38. In other words the CPU 40 has a function of acontrol section that controls changes in the drive signal that drivesthe transducer 2 b.

Further, according to the present embodiment, the CPU 40 has a functionof a cavitation generation control section (abbreviated to “CAVgeneration control section” in FIG. 3) 40 a that, by using thecavitation level signal Sc, controls output of a drive signal so as tomaintain a cavitation generation amount at a value that is set by thesetting section 24.

The CPU 40 determines the cavitation generation level based on the levelof the cavitation level signal Sc.

FIG. 4A is a view that shows the frequency spectrum distribution of thevoltage signal Sv when a cavitation is not generated (time ofnon-generation of cavitations) and when a cavitation is generated (timeof cavitation generation) by the transducer 2 b that is driven by adrive signal of the ultrasound driving apparatus 5. In this connection,in FIG. 4A a resonance frequency f res is 47 kHz.

Irrespective of the existence/non-existence of cavitation generation,the voltage signal Sv has a highest peak at the resonance frequency fres (47 kHz). When a cavitation is not generated, the voltage signal Svdoes not have a prominent peak at a frequency other than the resonancefrequency f res.

In contrast, when a cavitation is generated, at frequencies other thanthe resonance frequency f res, the level of the voltage signal Sv ishigher than a time when a cavitation is not generated.

More specifically, at a time when a cavitation is generated, the levelof subharmonics as frequencies of divisors such as ½ or ¼ of theresonance frequency f res or of differences of these divisors becomesconsiderably higher than at a time when a cavitation is not generated,and the level of a frequency component other than a subharmonic alsobecomes higher than when a cavitation is not generated.

Therefore, a cavitation generation level can be detected by detectingsignal levels for the voltage signal Sv as described above, excludinglevels in the vicinity of the resonance frequency f res thereof.

The cavitation level signal Sc as an output signal of the filter circuit39 is inputted into the CPU 40 that constitutes the output controlsection that controls driving of the transducer 2 b (in other words,ultrasound vibrations of the distal end member 2 e) and the cavitationgeneration control section 40 a.

The CPU 40 outputs to the differential amplifier 41 side an outputcurrent setting signal that corresponds to a value obtained bysubtracting the cavitation level signal Sc from the cavitation levelsetting value (also referred to as “cavitation setting value”) Scs thatis set at the setting section 24 by the surgeon. Thus, the settingsection 24 is provided with setting means with which the surgeondesignates and sets (or inputs and sets) the generation level ofcavitations.

Under control of the CPU 40, by means of the following closed loop,output of the drive signal is controlled so to maintain the value of thecavitation setting value Scs that is set by the setting section 24.

A current signal Si in the drive signal is also inputted into thedifferential amplifier 41. In this connection, although the currentsignal Si is actually detected by, for example, a current sensor or thelike that detects the current of a drive signal that is provided insidethe current/voltage detecting circuit 35, in FIG. 3 the current signalSi that is detected is illustrated in a simplified form.

The differential amplifier 41 outputs to the multiplier 32 a signal of adifferential value that is obtained by subtracting the current signal Sifrom the output current setting signal.

The multiplier 32 multiplies a value of another input end side intowhich is inputted a signal from the differential amplifier 41 by theoscillation signal from the oscillating circuit 31, and outputs theresult to the amplifier 33. In this case, the value of the other inputend side is a value obtained by adding the output signal of thedifferential amplifier 41 (subtracting when the output signal of thedifferential amplifier 41 is negative) to a standard value 1.

Accordingly, the current signal Si in the drive signal is controlled bya closed loop system so that a value of an output current setting signalthat is outputted from the CPU 40 is maintained as an averaged constantcurrent value. In this manner, the output value of a drive signalsupplied to the transducer 2 b is controlled.

In this connection, a time constant of a control system based on thecurrent signal Si of the drive signal is, for example, around 8 ms, andthe current signal Si changes within the range of this time constant.

An operation signal that switches output of a drive signal from the footswitch 8 “on” or “off” is inputted to the CPU 40, and control isperformed to switch output of the drive signal “on” or “off” inaccordance with the operation signal.

Further, the CPU 40 is connected with the display section 23 provided onthe front panel or the like, and an ultrasound output value or the likeis displayed on the display section 23. FIG. 4B and FIG. 4C illustratean example of the filter characteristics of the filter circuit 39, andFIG. 5 shows a configuration example thereof.

FIG. 4B illustrates a case in which characteristics are set that allow afrequency band of one portion of a low frequency side to pass through.More specifically, FIG. 4B illustrates a case in which characteristicsare set that allow a frequency band including a subharmonic (divisor) of½ of the resonance frequency f res to pass through.

FIG. 4C illustrates a case in which characteristics are set to a bandthat allows frequencies from around 5% of the resonance frequency f resto a frequency that is 5% lower than the resonance frequency f res (i.e.a frequency equal to 95% of the resonance frequency f res) to passthrough.

FIG. 4D illustrates a case in which, in addition to the bandcharacteristics shown in FIG. 4C, band characteristics are set thatallow frequencies from around 5% higher than the resonance frequency fres to a frequency that is 5% lower than a frequency (2 f res) of asecond-order harmonic wave of the resonance frequency f res to passthrough.

The filter circuit 39 shown in FIG. 5 includes, for example, a pluralityof bandpass filters (abbreviated as “BPF” in FIG. 5) 43 a, 43 b, . . . ,43 n; switches 44 a, 44 b, . . . , 44 n; wave detectors 45 a, 45 b, . .. , 45 n; and an integrator 46.

In this connection, a passing frequency band of the bandpass filters 43a, 43 b, . . . , 43 n is denoted in abbreviated form as fa, fb, . . . ,and fn. The relationship between the passing frequency bands in thiscase is, for example, fa<fb< . . . <fn.

A selection can be made to switch the switches 44 a, 44 b, . . . , 44 n“on” or “off”, for example, by making a setting from the setting section24 via the CPU 40. In this case, a configuration may also be adoptedthat enables a direct selection from the setting section 24.

By selecting whether to switch the switches 44 a, 44 b, . . . , 44 n“on” or “off”, an arbitrary passing frequency band can be set. Afterfrequency components that have passed through the switches 44 a, 44 b, .. . , 44 n that have been switched “on” are detected by the wavedetectors 45 a, 45 b, . . . , 45 n, the frequency components areintegrated at the integrator 46.

The integrated signal obtained by integration at the integrator 46 isoutputted to the CPU 40 as the cavitation level signal Sc. Anaccumulator may be used instead of the integrator 46.

A configuration may also be adopted in which, instead of integrating atthe filter circuit 39, integration is performed on the CPU 40 side.

Operations in the ultrasound driving apparatus 5 configured in thismanner will now be described referring to FIG. 6. FIG. 6 is a view thatshows a method of controlling an ultrasound operation that includescavitation generation control according to the ultrasound drivingapparatus 5.

For example, as shown in FIG. 2, the surgeon connects a handpiece (inFIG. 2, the handpiece 2 that is mainly for performingcoagulation/dissection) to be used in the treatment to the ultrasounddriving apparatus 5 via an ultrasound cable.

Further, as shown in step S1, the surgeon performs initial settings suchas setting the cavitation setting value Scs using the setting section 24in accordance with the living tissue to be treated (i.e. the site to betreated).

Subsequently, using an unshown trocar, the surgeon inserts an endoscopeand the probe 2 a of the handpiece 2 into the abdomen or the like of thepatient. The surgeon then sets the distal end side of the probe 2 a inthe vicinity of the treatment target site inside the body underobservation using the endoscope, as shown in step S2.

Next, in step S3, the surgeon switches the foot switch 8 “on” to starttreatment by ultrasound. A drive signal is applied to the transducer 2 bof the handpiece 2 from the ultrasound driving apparatus 5, and thetransducer 2 b vibrates at an ultrasound frequency.

The ultrasound vibrations are transmitted to the distal end member 2 eon the distal end side of the probe 2 a, and as shown in step S4, thedistal end member 2 e makes ultrasound vibrations at the resonancefrequency f res of the transducer 2 b.

In this case, the ultrasound driving apparatus 5 controls so as to tracka state in which the transducer 2 b is driven with the resonancefrequency f res thereof by means of the resonance frequency trackingsection 37 using the PLL circuit 36. Accordingly, the transducer 2 bmakes ultrasound vibrations at the resonance frequency f res, andfurther, the distal end member 2 e of the distal end section also makesultrasound vibrations at the resonance frequency f res.

Further, in this case, when a cavitation is generated by ultrasoundvibrations of the distal end member 2 e, the distal end member 2 ereceives a force produced by breaking of small bubbles caused bygeneration of the cavitation, and that force affects the ultrasoundvibrations of the transducer 2 b from the distal end member 2 e.Subsequently, as shown in FIG. 4A, a frequency component produced by thecavitation is superimposed on the original drive signal. As describedabove, the frequency spectrum of the original drive signal enters astate of having a distorted frequency spectrum due to generation of thecavitation.

Subsequently, as shown in step S5, the CPU 40 detects the cavitationgeneration level from the cavitation level signal Sc that is detected bythe filter circuit 39 from the drive signal.

Next, in step S6, the CPU 40 controls the output of the drive signal viathe differential amplifier 41 so that the detected cavitation generationlevel maintains a cavitation level setting value Scs that is previouslyset by the setting section 24. More specifically, the CPU 40 performsoutput control of the drive signal so as to maintain the set cavitationsetting value Scs.

Under this control, as shown in step S7, the surgeon performs treatmentsuch as coagulation and dissection by means of ultrasound vibrations.

FIG. 7 is a view that illustrates operations to detect the cavitationlevel and to control the generation level of cavitations, i.e. thecavitation level, in accordance with the detection result according tosteps S5 and S6 shown in FIG. 6. In step S11, the filter circuit 39detects a predetermined frequency component excluding the frequency of adrive signal as the cavitation level signal Sc.

Next, in step S12, the CPU 40 compares the cavitation level signal Scthat is outputted from the filter circuit 39 with the cavitation settingvalue Scs.

Subsequently, as shown in step S13, the CPU 40 determines the sizerelationship between the cavitation level signal Sc and the cavitationsetting value Scs. When the comparison result is Sc>Scs, as shown instep S14 the CPU 40 performs control so as to reduce the output currentsetting signal, and thereafter returns to the processing of step S11.

When the comparison result is the opposite, i.e. when Sc<Scs, as shownin step S15, the CPU 40 controls so as to increase the output currentsetting signal, and thereafter returns to the processing of step S11.

Further, when the comparison result is Sc=Scs, as shown in step S16, theCPU 40 controls so as not to change the output current setting signal(maintain the output current). In this control state, the surgeonperforms the treatment by ultrasound in step S7 as shown in FIG. 6.

By performing this control, the CPU 40 controls so as to maintain thecavitation generation level at the cavitation setting value Scs set bythe setting section 24.

According to the present embodiment that performs treatment with respectto living tissue as a treatment target by this control, it is possibleto detect the generation of cavitations using a simple configuration,and the generation level of cavitations can be controlled so as tomaintain a set cavitation level setting value Scs.

In this case, generation of cavitations and the level of generation canbe accurately detected from a voltage signal or the like of a frequencycomponent excluding the drive frequency or the resonance frequency f resbased on the filter circuit 39 in a drive signal that drives thetransducer 2 b.

According to the present embodiment, a treatment function for carryingout medical treatment can be enhanced by effectively utilizing thegeneration of cavitations.

In this connection, Japanese Patent Application Laid-Open PublicationNo. 2008-188160 as an example of the related art discloses an ultrasoundoperation apparatus that has a drive circuit that drives a handpiece ata frequency and amplitude that correspond to an alternating current. Theultrasound operation apparatus includes a cavitation suppression circuitthat has conversion means that converts an output end voltage of thedrive circuit into a direct current voltage, comparison means thatcompares the direct current voltage from the conversion means with apredetermined threshold value, and voltage control means that, in a casein which the comparison result from the comparison means exceeds thethreshold value, lowers the voltage value of the alternating current.

According to this example of the related art, it is described thatpractical application is made of the fact that when a load state of apiezo element included in a vibration generation section is changed bygeneration of a cavitation, although an alternating voltage valueoutputted by an output circuit (provided with a drive circuit) changesvery little, the output voltage value fluctuates in proportion to theload state.

In contrast to the related art example, the present embodiment isconfigured so as to detect a cavitation using at least one member of thegroup consisting of a voltage value, an impedance value, and a currentvalue of a frequency component excluding the vicinity of a frequencyused for driving in a drive signal.

Accordingly, the present embodiment is capable of adequately decreasingthe influence of a drive signal to detect the existence/non-existence ofcavitation generation and the generation level with a high accuracy.

That is, according to the present embodiment, by detecting frequencycomponents excluding the vicinity of the frequency of a drive signal, itis possible to detect, for example, a cavitation generation level basedon the level of a cavitation level signal Sc, without receivingvirtually any influence by the output level of the drive signal.

In this case, the existence/non-existence of cavitation generation canbe determined by determining whether or not the level of the cavitationlevel signal Sc is greater than a threshold value that is close to 0.Further, the cavitation generation level can also be detected even in acase in which, during an operation, the surgeon changes the settingvalue from the setting section 24 so as to change the output level ofthe drive signal.

In contrast, according to the related art example it is necessary topreviously set a threshold value for detecting generation of acavitation, and it is considered that it is necessary to change thethreshold value in a case in which the output of the drive circuit ischanged.

The related art example further discloses a configuration that isprovided with a microphone that detects the continuous sound of afrequency that is generated at the time of a cavitation, in whichcavitation suppression is performed with an audio signal that themicrophone outputs.

However, in this case it is necessary to provide the microphone at adistal end side of an elongated probe 2 a that can be inserted into thebody.

In contrast, according to the present embodiment, theexistence/non-existence of cavitation generation and the generationlevel can be detected on the side of the ultrasound driving apparatus 5that is disposed outside the body. Further, with respect to theconfiguration of the probe itself, an existing probe and handpiece canbe employed.

Accordingly, the present embodiment has a merit of being easy to applyeven in the case of an existing handpiece that includes a transducer.

Second Embodiment

FIG. 8 illustrates a configuration of an ultrasound operation apparatus21B according to the second embodiment of the present invention. For thefirst embodiment, a configuration was described that automaticallycontrols a cavitation generation level so that the level reaches a valuethat is set at the setting section 24.

In contrast, the present embodiment has a configuration that includes anotification section that notifies a cavitation generation level to thesurgeon as a user by quantitatively displaying the generation level.Further, the configuration allows the surgeon to manually set a settingvalue of the setting section 24 so as to set a desired generation levelfrom the displayed generation level.

The ultrasound operation apparatus 21B has an ultrasound drivingapparatus 5B that includes, in the configuration of the ultrasounddriving apparatus 5 shown in FIG. 3, an A/D conversion circuit 51 thatsubjects an output signal of the filter circuit 39 to A/D conversion,and an indicator 52 as a notification section that quantitativelydisplays an cavitation generation level by means of an output signal ofthe A/D conversion circuit 51.

In this connection, according to the present embodiment the CPU 40 doesnot have the cavitation generation control section 40 a. As amodification example of the present embodiment, a configuration may beadopted in which, as indicated by the chain double-dashed line, thecavitation level signal Sc is inputted to the CPU 40, and a selectioncan be made between a control mode that performs automatic control and aconstant current control mode that is set by a manual setting as in thefirst embodiment. Therefore, the cavitation generation control section40 a is indicated with a chain double-dashed line in FIG. 8.

A cavitation level signal Sc that is outputted from the filter circuit39 is subjected to A/D conversion by the A/D conversion circuit 51. Thedigital signal that has undergone A/D conversion corresponds to thecavitation generation level.

Subsequently, for example, a plurality of LEDs 53 that constitute anindicator 52 are caused to emit light by the digital signal. Forexample, the number of LEDs 53 that emit light changes approximately inproportion to the cavitation generation level. In FIG. 8, for example,two LEDs 53 are emitting light, as indicated by the diagonal lines. Whenthe cavitation generation level increases further, more of the LEDs 53emit light.

An output current setting value that is set by the surgeon is inputtedto the CPU 40 from the setting section 24B. That is, the setting section24B constitutes setting means that sets (inputs) an output currentsetting value of the drive section. The CPU 40 outputs an output currentsetting signal of a value that corresponds to the output current settingvalue to the differential amplifier 41 so as to maintain the outputcurrent setting value received from the setting section 24B.

In the present embodiment, output of a drive signal to the transducer 2b (more generally, a transducer Ib) is controlled by the CPU 40 so as tomaintain the output current setting value. The remaining configurationis the same as that of the first embodiment.

According to the present embodiment, the surgeon can check thecavitation generation level using the display of the number of LEDs 53emitting light on the indicator 52. When the surgeon checks thecavitation generation level and wishes to increase the cavitationgeneration level, it is sufficient for the surgeon to increase theoutput current setting value of the setting section 24B.

FIG. 9 shows a flowchart of an example of usage of the presentembodiment. For example, similarly to the case shown in FIG. 2, thesurgeon connects the handpiece 2 to the ultrasound driving apparatus 5B.

Further, the surgeon performs initial settings such as setting theoutput current setting value by means of the setting section 24B, asshown in step S21, in accordance with the living tissue to be treated.

Subsequently, as shown in step S22, for example, under observation withan endoscope, the surgeon sets the distal end side of the probe 2 a inthe vicinity of a treatment target site inside the body.

Next, in step S23, the surgeon switches “on” the foot switch 8 to starttreatment by ultrasound. A drive signal is applied from the resonancefrequency tracking section 37 included in the drive section of theultrasound driving apparatus 5B to the transducer 2 b of the handpiece2, so that the transducer 2 b generates ultrasound vibrations.

The ultrasound vibrations are transmitted to the distal end member 2 eon the distal end side of the probe 2 a and, as shown in step S24, thedistal end member 2 e makes ultrasound vibrations at the resonancefrequency f res of the transducer 2 b.

Further, in this case, based on the output signal of the filter circuit39, the indicator 52 displays the generation level of cavitationsgenerated by the ultrasound vibrations of the distal end member 2 e, tothus notify the surgeon by means of the display.

The surgeon refers to the cavitation generation level as shown in stepS26, and effectively utilizes the cavitations to perform treatment byultrasound. In this case, when the surgeon attempts to increase thegeneration level of cavitations to perform treatment, it is sufficientto perform a setting to increase the output current setting value bymeans of the setting section 24B.

Thus, the surgeon can check the cavitation generation level displayed onthe indicator 52, and perform treatment utilizing cavitations.

According to the present embodiment, the surgeon can perform treatmentthat effectively utilizes cavitations by increasing the cavitationgeneration level or the like by setting the setting section 24B.

In this connection, apart from notifying the surgeon using a displaydevice, the notification section may be configured, for example, tonotify the surgeon with a sound or the like.

A configuration may also be adopted in which the function of thenotification section of the indicator 52 is provided in the displaysection 23. For example, in the embodiments described after FIG. 8,although the indicator 52 is not shown, the function of the indicator 52may be performed by the display section 23. In this case, as shown bythe chain double-dashed line in FIG. 8, a configuration may be adoptedin which the cavitation level signal Sc of the filter circuit 39 isinputted to the CPU 40 and a signal corresponding to the cavitationgeneration level from the CPU 40 is outputted to the display section 23.

Further, as described above, the configuration of a modification examplethat includes the control mode of the first embodiment can also beadopted. In this case, the surgeon can select between a control modethat allows manual control and a control mode that controlsautomatically, and use the selected control mode.

Third Embodiment

Next, the third embodiment of the present invention is described withreference to FIG. 10. The present embodiment has a control switchingsection or a control selection section that can select two control modesor control patterns that include a normal constant current (constantamplitude) control mode and a cavitation control mode which havedifferent control contents so as to perform treatment by ultrasoundvibrations.

Further, in a modification example of the present embodiment, it is alsopossible to perform control that sets a control mode in accordance withthe type of handpiece as a treatment instrument that performs treatmentby ultrasound vibrations and the usage situation.

An ultrasound operation apparatus 21C of the third embodiment shown inFIG. 10 includes an ultrasound driving apparatus 5C that is inaccordance with the ultrasound driving apparatus 5 of the ultrasoundoperation apparatus 21 shown in FIG. 3 and is further provided with arelay device 61 that switches between the filter circuit 39 and the CPU40 constituting an output control section using a switching controlsignal.

The relay device 61 is switched on/off by a switching control signalfrom the CPU 40 to thereby switch the control mode. More specifically,the output control section constituted by the CPU 40 further includes acontrol switching section that switches the control mode.

Further, the ultrasound driving apparatus 5C according to the presentembodiment, for example, includes a setting section 24C as shown in FIG.11.

The setting section 24C is provided with a constant current controlswitch 62 a with which the surgeon selectively designates the constantcurrent control mode and a cavitation control switch 62 b with which thesurgeon selectively designates the cavitation control mode.

The setting section 24C is provided with level switches 63 a, 63 b, and63 c that set an output level in the case of both control modes to aplurality of levels. For example, the level switches 63 a, 63 b, and 63c set an output level to LV1, LV2, and LV3, respectively.

Accordingly, the setting section 24C outputs to the CPU 40 a controlmode signal that designates the constant current control mode or thecavitation control mode, and a setting value that sets the output level.

In this connection, FIG. 11 illustrates a configuration in which levelswitches 63 j (j=a to c) are commonly used when a level is set in bothcontrol modes. However, a configuration may also be adopted in which aplurality of level switches that are dedicated to each control mode areprovided, for example.

In the configuration shown in FIG. 10, the CPU 40 performs outputcontrol in accordance with the control mode setting made at the settingsection 24C by the surgeon.

More specifically, when the constant current control mode is selected,the CPU 40 outputs a switching control signal that switches the relaydevice 61 to “off”. Subsequently, the CPU 40 outputs an output currentsetting signal to the differential amplifier 41 so as to maintain theoutput level according to the level switches 63 j (j=a to c) at thesetting section 24C.

In contrast, when the cavitation control mode is selected, the CPU 40outputs a switching control signal to switch the switch of the relaydevice 61 to “on”. Accordingly, a cavitation level signal Sc from thefilter circuit 39 is inputted to the CPU 40 via the relay device 61 thathas been switched “on”.

The CPU 40 outputs the cavitation level signal Sc to the differentialamplifier 41 as an output current setting signal so as to maintain theoutput level according to the level switches 63 j (j=a to c) at thesetting section 24C that are set as the cavitation control mode by thesurgeon.

The remaining configuration is the same as that of the first embodiment.A representative example of the control method according to the presentembodiment will now be described using FIG. 12. Since the presentcontrol method is similar to the first embodiment, the description willbe made with reference to FIG. 6.

First, as shown in step S1′, the surgeon performs initial settingsincluding selection of the control mode. Thereafter, the processing ofstep S2 to step S4 is performed in the same manner as in FIG. 6. In stepS31, the next step after step S4, the CPU 40 determines whether or notthe control mode is the constant current control mode. When the controlmode is the constant current control mode, as shown in step S32, the CPU40 performs output control (constant current control) corresponding tothe settings of the setting section 24C. Next, the CPU 40 proceeds tostep S7.

In contrast, when the result determined in step S31 is that the controlmode is not the constant current control mode, that is, when the controlmode is the cavitation control mode, similarly to step S5 in FIG. 6, theCPU 40 detects the cavitation generation level from the output signal ofthe filter circuit 39. Further, at the next step S6, the CPU 40 performsoutput control of the drive signal including cavitation generation levelcontrol so as to maintain the level set by the setting section 24C basedon the detected cavitation level signal Sc.

Subsequently, in step S7, the next step after step S6, the surgeonperforms treatment by ultrasound.

According to the present embodiment, ultrasound treatment can beperformed according to the normal constant current control, andultrasound treatment can also be performed in a state in which automaticcontrol is performed so as to maintain the cavitation generation level.

Further, the surgeon can perform treatment by ultrasound by changing thecontrol mode in accordance with the handpiece I or the probe Ia that isactually used as well as the usage state.

In this connection, with respect to the constant current control mode,in addition to a control method that performs constant current controlirrespective of the generation of cavitations, a configuration may beadopted that suppresses cavitation generation and performs constantcurrent control. For example, as indicated by the chain double-dashedline in FIG. 11, a configuration may be adopted that is provided with aswitch 64 that switches between a mode that performs constant currentcontrol irrespective of the generation of cavitations and a mode thatsuppresses cavitation generation and performs constant current control.

For example, when the switch 64 has been switched “off”, the CPU 40performs constant current control irrespective of the generation ofcavitations. In contrast, when the switch 64 has been switched “on”, theCPU 40 performs constant current control in which the generation ofcavitations is suppressed.

FIG. 13 illustrates the configuration of an ultrasound operationapparatus 21D as a first modification example. As described hereunder,the present modification example is provided with an identificationsection that identifies a handpiece I, and is configured to be capableof switching the control mode in accordance with the identificationresult.

The ultrasound operation apparatus 21D is according to the ultrasoundoperation apparatus 21C shown in FIG. 10, in which each handpiece I (inFIG. 13, I=2), for example, includes a ROM Ih that forms an identifierthat generates handpiece classification information (also referred tosimply as “classification signal”) that is contained, for example, inthe proximal end section of the probe Ia.

Further, an ultrasound driving apparatus 5D includes a communicationcircuit 66 that reads out a handpiece classification signal that isstored in the ROM Ih from the handpiece I that is connected via theultrasound cable 14 to the ultrasound driving apparatus 5D. Thecommunication circuit 66 sends the handpiece classification signal thatis read out to the CPU 40.

The CPU 40 can identify the type of handpiece I, the type of transducerIb mounted to the handpiece I, and the shape or state of the distal endsection of the probe Ia of the handpiece I and the like based on thehandpiece classification signal from the communication circuit 66.

In accordance with the handpiece classification signal, the CPU 40, forexample, refers to information stored in a flash memory 67 toautomatically select and set one of the constant current control modeand the cavitation control mode.

Information that indicates which control mode to use in correspondencewith a handpiece classification signal is previously stored in the flashmemory 67. In this connection, the information stored in the flashmemory 67 can be changed or updated, for example, from the settingsection 24C via the CPU 40.

For example, in a case in which the handpiece 2 is connected to theultrasound driving apparatus 5D, the CPU 40 selects the constant currentcontrol mode by referring to the corresponding information. In contrast,when the handpiece 3 is connected to the ultrasound driving apparatus5D, the CPU 40 selects the cavitation control mode by referring to thecorresponding information.

Further, in a case in which information that indicates that the controlmode is to be set (selected) manually from the setting section 24C isstored in the flash memory 67, the CPU 40 preferentially sets thecontrol mode that is selected manually by the surgeon from the settingsection 24C.

In this connection, the present modification example is not limited toan example in which respective handpiece classification signals arestored in the ROM Ih. For example, a configuration may also be adoptedin which the manufacturer's serial numbers or the like of the handpiecesare stored, and the CPU 40 refers to information stored in the flashmemory 67 based on the relevant serial number to identify theclassification or the like of the handpiece corresponding to the serialnumber.

The present modification example is not limited to a case that uses theROM Ih, and for example, a configuration may be adopted in whichidentification is performed using a resistance value, or in which thetype of handpiece or the like can be identified based on an on/off arrayof, for example, DIP switches that include a plurality of switchingelements.

Next, the operation of the present modification example is describedreferring to the flowchart shown in FIG. 14.

As shown in step S41, the surgeon connects the handpiece I to beactually used to the ultrasound driving apparatus 5D, and turns on thepower of the ultrasound driving apparatus 5D.

Thereupon, as shown in step S42, the CPU 40 acquires a classificationsignal of the handpiece I from the ROM Ih of the handpiece I via thecommunication circuit 66. That is, the CPU 40 identifies the type ofhandpiece I.

Next, as shown in step S43, the CPU 40 refers to information stored inthe flash memory 67 to determine based on the classification signal if,for example, a manual setting is to be performed.

As shown in step S44, in a case in which a manual setting is not to beperformed, that is, in a case in which the setting is to be performedautomatically, the CPU 40 automatically sets the control mode accordingto the classification signal. In other words, the CPU 40 automaticallyselects or automatically switches a single control mode among aplurality of control modes in accordance with an identification resultfrom the identification section.

In contrast, as shown in step S45, in the case of manual setting, theCPU 40 sets the control mode in accordance with a manual selection fromthe setting section 24C. Thus, the operation to set the control modeends. Following this operation to set the control mode, for example,after the initial settings, the operations of step S2 and thereafter inFIG. 12 are performed.

According to the present modification example, once the surgeonpre-registers information regarding control modes that the surgeondesires to use in accordance with the classification of handpieces inthe flash memory 67, thereafter a single control mode is automaticallyset from among a plurality of control modes in accordance with thepre-registered information. Thus, the ease of operation with respect totreatment performed by the surgeon can be enhanced.

The surgeon can also preferentially select the constant current controlmode or the cavitation control mode manually from the setting section24C and perform treatment.

FIG. 15 is a view that illustrates a configuration of an ultrasoundoperation apparatus 21E according to a second modification example.

The ultrasound operation apparatus 21E includes an ultrasound drivingapparatus 5E that is in accordance with the ultrasound driving apparatus5D of the ultrasound operation apparatus 21D shown in FIG. 13, with theexception that the ultrasound driving apparatus 5E does not have therelay device 61. In this case the cavitation level signal Sc of thefilter circuit 39 is inputted to the CPU 40.

The CPU 40 refers to the cavitation level signal Sc that is inaccordance with a control mode set according to the handpiececlassification signal or a control mode selected (set) from the settingsection 24C.

The operations of the present modification example are approximately thesame as the operations in the case illustrated in FIG. 13.

FIG. 16 is a view that illustrates an outline configuration of principalparts of an ultrasound operation apparatus 21F according to a thirdmodification example. The present modification example is configured tobe capable of detecting a change in a usage state in a specifictreatment instrument to automatically switch a control mode.

The ultrasound operation apparatus 21F includes an ultrasound drivingapparatus 5F that is, for example, in accordance with the ultrasounddriving apparatus 5E of the ultrasound operation apparatus 21E shown inFIG. 15, with the exception that the ultrasound driving apparatus 5Fdoes not include the communication circuit 66 provided in the ultrasounddriving apparatus 5E, and that a detection signal from a sensor 2 jprovided in a specific handpiece 2 is inputted to the CPU 40.

As shown in FIG. 16, for example, the sensor 2 j that is switched “on”from an “off” state by a pressing force is mounted at a position facinga moveable handle 19 a on a fixed handle 19 b in the handpiece 2.

The sensor 2 j detects an open/closed state of the handle 18 and, forexample, outputs an “on” detection signal when the handle 18 is in aclosed state and outputs an “off” detection signal when the handle 18 isin an open state.

The distal end members 2 e and 2 g on the distal end side of the probe 2a open and close in accordance with an open/closed state of the handle18. Accordingly, the sensor 2 j outputs a signal that has detected anopen/closed state of the distal end section (distal end members 2 e, 2g).

The CPU 40 switches the control mode in accordance with the detectionsignal of the sensor 2 j that detects the open/closed state of thedistal end section by means of opening/closing of the handle 18. In thisconnection, information relating to switching the control mode inaccordance with a detection signal of the sensor 2 j is, for example,stored in the flash memory 67.

FIG. 17 illustrates a flowchart of operations according to the presentmodification example. After the power supply of the ultrasound drivingapparatus 5F has been turned on, when the foot switch 8 is switched“on”, ultrasound is outputted as shown in step S51.

More specifically, the transducer 2 b generates ultrasound vibrationsupon application of a drive signal to the transducer 2 b, the ultrasoundvibrations are transmitted to the distal end member 2 e, and the distalend member 2 e makes ultrasound vibrations (abbreviated as “ultrasoundis outputted”).

As shown in step S52, the CPU 40 detects opening/closing of the handle18 based on the detection signal of the sensor 2 j and detects acavitation generation state based on the output signal of the filtercircuit 39.

In step S53, the CPU 40 determines whether or not the handle 18 isclosed. The surgeon, for example, opens the handle 18 (the distal endsection opens also) to perform exfoliating dissection treatment. Incontrast, the surgeon closes the handle 18 to performcoagulation/dissection treatment.

If the handle 18 is open, the CPU 40 proceeds to step S54 a, and if thehandle 18 is closed, the CPU 40 proceeds to step S54 b.

In steps S54 a and 54 b, the CPU 40 determines whether or notcavitations are generated (abbreviated to “is there a cavitation”). Instep S54 a, when the determined result is that there are no cavitations,the routine advances to step S55.

In step S55, the CPU 40 performs control to increase the ultrasoundoutput by a predetermined amount, and then returns to the processing ofstep S54 a. Accordingly, by the processing of steps S54 a and S55, whenthe state is one in which cavitations are not generated, the ultrasoundoutput increases to a level that generates a cavitation.

When it is determined in step S54 a that there are cavitations, theroutine proceeds to step S56 to maintain the ultrasound output state inwhich there are cavitations. The surgeon continues to perform treatmentby ultrasound in the ultrasound output state.

When the result determined in step S54 b is that there are cavitations,as shown in step S57, for example, after performing ultrasound outputfor a fixed time period the CPU 40 decreases or stops the ultrasoundoutput.

In contrast, when the result determined in step S54 b is that there areno cavitations, as shown in step S56, the ultrasound output ismaintained. Further, when the handpiece 2 is used with, as shown in FIG.2, the ultrasound driving apparatus 5 together with the high frequencyoutput apparatus 6 and outputting ultrasound for a fixed time period instep S57, for example, monitoring of a high-frequency impedance of theliving tissue may also be performed.

In a case in which living tissue that is treated by friction produced byultrasound undergoes carbonized denaturation to a certain degree, thehigh-frequency impedance changes.

The state of change in the high-frequency impedance may be monitored andthe ultrasound output may be reduced or stopped if the carbonizeddenaturation has proceeded to a certain degree and coagulation treatmenthas been performed.

In contrast, when the handle 18 is open, the CPU 40 performs controlthat increases the output of the drive signal so as to generatecavitations, and controls so as to maintain the ultrasound output in thestate in which cavitations are generated. The surgeon then performstreatment such as dissection or exfoliating dissection by ultrasoundutilizing cavitations.

Normally, when the surgeon places distal end members 2 e and 2 g in aclosed state and performs coagulation/dissection treatment, in mostcases it is desirable to suppress cavitations.

In some cases, however, the surgeon sets the distal end members 2 e and2 g in an open state and performs dissection or exfoliating dissectionusing only the distal end member 2 e that makes ultrasound vibrations,without grasping the living tissue that is the treatment target. In suchcase, the surgeon may desire to maintain a state in which cavitationsare generated, and perform treatment by increasing a function such asexfoliating dissection by means of the cavitations.

Thus, according to the present modification example, it is possible toselect a control mode that utilizes cavitations in accordance with anopen/closed state of the distal end section that is produced by anopening/closing operation of the handle by the surgeon.

According to the present modification example, since a configuration isadopted that changes a control mode of a drive signal in accordance witha usage state of the handpiece 2, it is possible to reduce the time andtrouble required for the surgeon to perform an operation to change acontrol mode while performing treatment. That is, according to thepresent modification example, the ease of operation with respect to anultrasound operation can be enhanced, and treatment utilizingcavitations can be performed.

Fourth Embodiment

Next, a fourth embodiment of the present invention is describedreferring to FIG. 18. FIG. 18 illustrates a configuration of anultrasound operation system 1B that includes the fourth embodiment. Thepresent embodiment monitors a suction amount that is actually suckedwith respect to a preset suction amount when water supply and suctionoperations are made to operate in response to each other when performingtreatment using ultrasound vibrations. According to the presentembodiment, when the actual suction amount is greater than the suctionamount that has been set, control is performed to maintain a cavitationoutput state in that state.

The ultrasound operation system 1B includes an ultrasound operationapparatus 21H of the fourth embodiment as well as a water supply/suctiondevice 7 that is used simultaneously with the ultrasound operationapparatus 21H.

The ultrasound operation apparatus 21H includes an ultrasound drivingapparatus 5H and the handpiece 3 that is connected to the ultrasounddriving apparatus 5H and the water supply/suction device 7.

The CPU 40 included in the ultrasound driving apparatus 5H is connectedvia a communication cable 12 to a CPU 86 that is included in a controlsection of the water supply/suction device 7. The two CPUs 40 and 86 canperform two-way communication.

The ultrasound driving apparatus 5H is in accordance with the ultrasounddriving apparatus 5C shown in FIG. 10, and also includes, for example, asettings storage section 68 and the like as described below.

In FIG. 18, the components from the oscillating circuit 31 to the PLLcircuit 36 are denoted by a resonance frequency tracking section 37 thatis constituted by those components.

According to the ultrasound driving apparatus 5H of the presentembodiment, the settings storage section 68 that stores informationrelating to setting values that are set at the setting section 24C and asetting section 91 of the water supply/suction device 7, for example, isconstituted by a flash memory.

Further, the setting section 24C is provided with a storage button (orstorage switch) 70 that performs an operation to instruct that settingvalue information be stored in the settings storage section 68.

The water supply/suction device 7 has a water supply section 87 thatsupplies water (the water in this case is, for example, physiologicalsaline) and a suction section 88 that performs sucking, a water supplycontrol section 89 and a suction control section 90 that control theoperations of the water supply section 87 and the suction section 88,respectively, the CPU 86 as a control section that performs overallcontrol of the water supply/suction device, a setting section 91 thatsets a water supply amount and a suction amount and the like (i.e.performs a water supply amount setting and a suction amount setting), adisplay section 92 that displays a water supply amount and a suctionamount and the like, and a foot switch 10 that performs operations toinstruct that water supply or suction be performed.

In this connection, in FIG. 18, the CPU 86 may also be configured tofulfill the functions of the water supply control section 89 and thesuction control section 90.

The water supply section 87 and the suction section 88 include a watersupply pump 87 a that constitutes a water supply drive section thatsupplies water to the inside thereof and a suction pump 88 a thatconstitutes a suction driving section that performs suction. The (watersupply pump 87 a of the) water supply section 87 and the (suction pump88 a of the) suction section 88 are connected to a water supply/suctionconnector 3 g of the handpiece 3 via a water supply/suction tube 16 thatincludes a water supply tube and a suction tube that are respectivelyconnected to a water supply connector and a suction connector.

When the surgeon operates the foot switch 10 to give an instruction tosupply water, the CPU 86 drives the water supply pump 87 a via the watersupply control section 89. Thereupon, the water supply pump 87 a pumpsphysiological saline to the vicinity of the living tissue that is thetreatment target from the opening of the distal end member 3 e via thewater supply tube and the conduit inside the handpiece 3.

Further, when the surgeon operates the foot switch 10 to give aninstruction to perform suction, the CPU 86 drives the suction pump 88 avia the suction control section 90. Thereupon, the suction pump 88 asucks, via the suction tube, a liquid or fluid in which the liquid thathas been supplied from the opening of the distal end member 3 e andtissue pieces and the like that were crushed or ablated by the distalend member 3 e are mixed.

The water supply amount generated by the water supply section 87 and thesuction amount generated by the suction section 88 are detected bymeasuring the respective amounts using a flow rate sensor or the likeinside the water supply section 87 and the suction section 88. The CPU86 sets the level of a water supply drive signal and a suction drivesignal that determine a water supply amount and a suction amount of thewater supply pump 87 a and the suction pump 88 a in accordance withsetting values from the setting section 91.

When treatment is performed utilizing cavitations as described below, ina case in which the actual suction amount is detected as an amount thatis greater than a suction amount set by the setting section 91, the CPU86 controls to maintains the cavitation output state.

Next, operations including a utilization method that utilizescavitations generated by the ultrasound operation system 1B aredescribed referring to FIG. 19.

The surgeon connects the handpiece 3 to the ultrasound driving apparatus5H and the water supply/suction device 7 as shown in FIG. 18, and turnson the power supply of the ultrasound driving apparatus 5H and the watersupply/suction device 7. Next, the surgeon presets the ultrasound outputand the suction amount and the like before starting an operation, asshown in step S91 of FIG. 19.

Subsequently, as shown in the next step S92, the surgeon resets theultrasound output and the suction amount immediately after starting theoperation. In step S92, the surgeon sets the ultrasound output and thesuction amount to appropriate values that are suitable for the relevantcase according to the state of the living tissue of the affected area onwhich treatment is to be performed as well as the preferences of thesurgeon who is actually performing the operation and the like.

As shown in the next step S93, the surgeon then operates the storagebutton 70 to store information for the state that has been reset in stepS92. By operating the storage button 70, information relating to thereset ultrasound output and suction amount is stored in the settingsstorage section 68 via the CPU 40.

Subsequently, as shown in step S94, the surgeon operates the footswitches 8 and 10 to activate the ultrasound driving apparatus 5H andthe water supply/suction device 7.

Further, as shown in step S95, the CPU 40 detects the cavitationgeneration level based on the cavitation level signal Sc from the filtercircuit 39. In this case, it is assumed that cavitations are beinggenerated.

Next, as shown in step S96, the CPU 86 of the water supply/suctiondevice 7 detects the actual suction amount. The CPU 86 sends thedetected suction amount to the CPU 40 via the communication cable 12.

As shown in step S97, the CPU 40 compares the reset suction amount(referred to as “set suction amount”) that has been stored in thesettings storage section 68 and the actual suction amount, and as shownin step S98, determines whether or not the set suction amount>the actualsuction amount. In accordance with the determined result, the CPU 40that performs cavitation generation control performs control to maintainthe cavitation generation state (output level state).

When the result determined by the CPU 40 in step S98 is affirmative, insome cases the surgeon may desire to reduce or stop the cavitationoutput level in that state. Accordingly, in this case, as shown in stepS99, the CPU 40 controls to reduce or stop the cavitation output.

In contrast, when the result determined by the CPU 40 in step S98 isnegative, that is, when the set suction amount≦the actual suctionamount, in some cases the surgeon may desire to maintain the cavitationoutput level in that state. Accordingly, in this case, as shown in stepS100, the CPU 40 controls so as to maintain the current cavitationoutput.

According to the present embodiment, when the set suction amount≦theactual suction amount, control is performed to maintain the cavitationoutput.

Fifth Embodiment

Next, a fifth embodiment of the present invention is described referringto FIG. 20A and the like. FIG. 20A shows the shape of a distal endsection of the handpiece 2 according to the fifth embodiment of thepresent invention. The distal end section of the handpiece 2 includes amoveable distal end member 2 g and a fixed distal end member 2 e thatopen/close in response to an opening/closing operation of the handle 18(see FIG. 2).

According to the present embodiment, the moveable distal end member 2 gand the fixed distal end member 2 e are provided with sawtooth-shapedconcavo-convex sections 94 a and 94 b, respectively, on opposingsurfaces. The surgeon performs coagulation/dissection treatment bygrasping a living tissue 95 as a treatment target between the twoconcavo-convex sections 94 a and 94 b.

By performing an operation to close the handle 18 from the state shownin FIG. 20A, the living tissue 95 is grasped between the concavo-convexsection 94 a of the moveable distal end member 2 g and theconcavo-convex section 94 b of the fixed distal end member 2 e, andenters a state in which the living tissue 95 is in close contact with asurface of each of the concavo-convex sections 94 a and 94 b.

FIG. 20B shows a state in which the living tissue 95 is in close contactwith the surface of the sawtooth-shaped concavo-convex section 94 b ofthe fixed distal end member 2 e that actually makes ultrasoundvibrations. In this state, by causing the fixed distal end member 2 e tomake ultrasound vibrations, cavitations 96 are generated in the livingtissue 95 in the vicinity of the surface of the concavo-convex section94 b (particularly, a surface forming a stepped surface with respect tothe longitudinal direction).

In the present embodiment, by employing a driving sequence asillustrated in FIG. 22A and the like as described later,coagulation/dissection treatment can be smoothly performed with respectto the living tissue 95 as the treatment target.

The shape of the distal end section in this case is not limited to theshape shown in FIG. 20A, and a structure may also be adopted that isprovided with rectangular concavo-convex sections 94 c and 94 d as shownin FIG. 20C.

Further, as shown in FIG. 20D and FIG. 20E, a structure may be adoptedin which concavo-convex sections 94 b, 94 d are provided only on thefixed distal end member 2 e, and the moveable distal end member 2 g isprovided with surfaces 94 e, 94 e that are level or smooth with respectto the opposing surfaces of the concavo-convex sections 94 b, 94 d.

FIG. 21 illustrates an ultrasound operation apparatus 21J of the presentembodiment. The ultrasound operation apparatus 21J has an ultrasounddriving apparatus 5J. The ultrasound driving apparatus 5J is, forexample, in accordance with the ultrasound driving apparatus 5 shown inFIG. 3, and is further provided with a driving sequence setting button97 with which the surgeon sets a driving sequence in the setting section24.

By switching the driving sequence setting button 97 “on”, the surgeoncan set a time (cycle) in which to perform treatment in a coagulationmode by ultrasound and a time in which to perform treatment in adissection mode, and can make a setting that switches between andactuates both modes.

In accordance with the setting of the driving sequence setting button97, the CPU 40 switches output of the drive signal according to thecycle at which the coagulation mode and the dissection mode are set.

In this case, in the dissection mode the CPU 40 controls so as tomaintain the set cavitations as described in the first embodiment, thatis, the CPU 40 causes the operation of the cavitation generation controlsection 40 a to function. In contrast, in the coagulation mode, the CPU40 controls so as to suppress cavitations and output a drive signal.

The remaining configuration is the same as that of the ultrasounddriving apparatus 5 shown in FIG. 3.

FIG. 22A illustrates a driving sequence in ultrasound treatmentaccording to the present embodiment. When the treatment using ultrasoundstarts at, for example, a time t0, the CPU 40 sets the control mode tothe coagulation mode and outputs a drive signal to the transducer 2 bfrom the resonance frequency tracking section 37 constituting the drivesection for a time (t1−t0) that has been set by the setting section 24.

The ultrasound vibrations generated by the transducer 2 b are applied tothe living tissue 95 from the distal end section of the probe 2 a toperform coagulation treatment. In this case, the CPU 40 monitors theoutput signal of the filter circuit 39, and controls the ultrasoundoutput so as to suppress generation of cavitations.

When the time (t1−t0) for treatment in the coagulation mode lapses, theCPU 40 switches to the dissection mode at the time t1, and outputs thedrive signal to the transducer 2 b from the resonance frequency trackingsection 37 for a time (t2−t1) that has been set by the setting section24.

The ultrasound vibrations generated by the transducer 2 b are applied tothe living tissue 95 from the distal end section of the probe 2 a toperform dissection treatment. In this case, the CPU 40 monitors theoutput signal of the filter circuit 39, and controls the ultrasoundoutput so as to maintain the state in which cavitations are generated.That is, the CPU 40 causes the operations of the cavitation generationcontrol section 40 a to function (denoted by “ON” in FIG. 22A), toperform dissection treatment by increasing the dissection functionutilizing cavitations.

When the time (t2−t1) for treatment in the dissection mode lapses, theCPU 40 switches to the coagulation mode at the time t2, and performssimilar control for a time (t3−t2) that has been set by the settingsection 24. The CPU 40 continues to repeat operations alternately in thecoagulation mode and the dissection mode in this manner until times t4and t5. Subsequently, upon performing treatment in the dissection modefrom the time t5 to a time t6, the CPU 40 ends thecoagulation/dissection treatment with respect to the living tissue thatis the treatment target.

Although an example in which the coagulation mode and the dissectionmode are switched and performed a plurality of times is described usingFIG. 22A, as shown in FIG. 22B, a configuration may also be adopted inwhich the times for performing the coagulation mode and the dissectionmode are lengthened to a time from t0 to ta and a time from ta to tb,respectively, so as to, for example, perform coagulation/dissectiontreatment with respect to the living tissue 95 that is the treatmenttarget one time each in both modes. Furthermore, the present inventionis not limited to the examples shown in FIG. 22A and FIG. 22B, and aconfiguration may also be adopted so as to perform treatment using adriving sequence that represents an intermediate sequence with respectto the driving sequences shown in FIG. 22A and FIG. 22B.

Having described the preferred embodiments of the invention referring tothe accompanying drawings. It should be understood that the presentinvention is not limited to those precise embodiments and variouschanges and modifications thereof could be made by one skilled in theart without departing from the spirit or scope of the invention asdefined in the appended claims.

What is claimed is:
 1. An ultrasound operation apparatus for treating aliving tissue, comprising: an ultrasound transducer configured togenerate ultrasound vibrations; a probe that has a proximal end sectionthat is operationally coupled with the ultrasound transducer, and adistal end section that makes ultrasound vibrations, the probe beingconfigured to transmit the ultrasound vibrations generated by theultrasound transducer from the proximal end section to the distal endsection; a resonance frequency tracking section configured toautomatically adjust a frequency of a drive signal so as to track aresonance frequency of the ultrasound transducer to cause the distal endsection to make ultrasound vibrations at the resonance frequency; asetting section configured to set a setting value at a cavitation level;a detection section configured to detect a signal level of a frequencycomponent signal obtained by integration of the drive signal in apredetermined frequency band excluding the resonance frequency based ona drive signal adjusted by the resonance frequency tracking section; anda control section configured to control an output of the drive signal soas to generate a cavitation or to increase or maintain the cavitationwith respect to the setting value set by the setting section inaccordance with a detection result of the detection section.
 2. Theultrasound operation apparatus according to claim 1 wherein thedetection section detects at least one of a voltage value, a currentvalue, and an impedance value of a frequency component at a frequencyother than the resonance frequency of the drive signal as the signallevel.
 3. The ultrasound operation apparatus according to claim 1,wherein the control section controls the drive signal based on thesignal level detected by the detecting section so as to maintain thegeneration amount of the cavitation level corresponding to the settingvalue that is set by the setting section.
 4. The ultrasound operationapparatus according to claim 1, wherein the signal level is a signalcomprising an integral of frequency components at frequencies that aregreater than the resonance frequency and smaller than a second-orderharmonic wave of the resonance frequency.
 5. The ultrasound operationapparatus according to claim 1, wherein the signal level is a signalcomprising an integral of frequency components in at least one of afrequency band from 5% to 95% of the resonance frequency and a frequencyband from 105% to 195% of the resonance frequency.
 6. The ultrasoundoperation apparatus according to claim 1, comprising a notificationsection configured to notify a generation level of the cavitationcorresponding to the signal level detected by the detection section. 7.The ultrasound operation apparatus according to claim 1, wherein thecontrol section switches between a plurality of control modes in whichcontrol contents are different.
 8. The ultrasound operation apparatusaccording to claim 7, further comprising a control switching sectionconfigured to set the control modes.
 9. The ultrasound operationapparatus according to claim 7, wherein the control section identifiesone or more of a type of the probe, the ultrasound transducer, or ashape or a state of use of the distal end section, and switches thecontrol mode in accordance with a result of the identification.
 10. Theultrasound operation apparatus according to claim 1, wherein the distalend section comprises a concavo-convex shape.
 11. An ultrasoundoperation system, comprising: an ultrasound transducer configured togenerate ultrasound vibrations; a probe that has a proximal end sectionthat is operationally coupled with the ultrasound transducer, and adistal end section that makes ultrasound vibrations, the probe beingconfigured to transmit the ultrasound vibrations generated by theultrasound transducer from the proximal end section to the distal endsection; a resonance frequency tracking section configured toautomatically adjust a frequency of a drive signal so as to track aresonance frequency of the ultrasound transducer, to cause the distalend section to make ultrasound vibrations at the resonance frequency; asetting section configured to set a setting value at a cavitation level;a detection section configured to detect a signal level of a frequencycomponent signal obtained by integration of the drive signal in apredetermined frequency band excluding the resonance frequency based ona drive signal adjusted by the resonance frequency tracking section; asuction driving section configured to suck a liquid around the distalend section; a suction setting section configured to set a suctionamount; a suction control section configured to control the suctiondriving section in accordance with the setting by the setting section;and a control section configured to control the vibrations of the drivesignal of the ultrasound transducer so as to maintain generation of acavitation or a generation amount of the cavitation in accordance withthe detection section signal and the suction amount.
 12. A cavitationutilization method for treating a living tissue, comprising: a step ofgenerating ultrasound vibrations by an ultrasound transducer; a step oftransmitting the ultrasound vibrations to a distal end section of aprobe by the ultrasound transducer, the probe having a proximal endsection that is operationally coupled with the ultrasound transducer,and the distal end section that generates ultrasound vibrations; a stepof automatically adjusting, by a resonance frequency tracking section, afrequency of a drive signal so as to track a resonance frequency of theultrasound transducer to cause the distal end section to make ultrasoundvibrations at the resonance frequency; a step of setting a setting valueat a cavitation level by a setting section; a step of detecting, by adetection section, a signal level of a frequency component signalobtained by integration of the drive signal in a predetermined frequencyband excluding the resonance frequency based on a drive signal adjustedby the resonance frequency tracking section; and a step of controlling,by a control section, an output of the drive signal so as to generate,increase or maintain a cavitation with respect to the cavitation levelcorresponding to the setting value set by the setting section inaccordance with a detection result of the detection section.
 13. Thecavitation utilization method according to claim 12, wherein thedetection section detects at least one of a voltage value, a currentvalue, and an impedance value of a frequency component at a frequencyother than the resonance frequency of the drive signal as the cavitationlevel signal.